21255456056 has 32 divisors (see below), whose sum is σ = 40704325200. Its totient is φ = 10403320320.

The previous prime is 21255456041. The next prime is 21255456059. The reversal of 21255456056 is 65065455212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21255456059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74465 + ... + 219216.

Almost surely, 2^21255456056 is an apocalyptic number.

It is an amenable number.

21255456056 is a deficient number, since it is larger than the sum of its proper divisors (19448869144).

21255456056 is a wasteful number, since it uses less digits than its factorization.

21255456056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 293879 (or 293875 counting only the distinct ones).

The product of its (nonzero) digits is 360000, while the sum is 41.

The spelling of 21255456056 in words is "twenty-one billion, two hundred fifty-five million, four hundred fifty-six thousand, fifty-six".